Short at High Intensity vs. Long at Lower Intensity

Seginns
Seginns Posts: 39
edited September 30 in Fitness and Exercise
Is there a difference in how much body fat is used when choosing to work out for a short period (ex., 20 minutes) at a high intensity verses working out for a longer time (ex., 40 minutes) at a lower intensity? I tend to work out for short periods, since I usually don't have more than 30 minutes, but someone suggested to me that I may use more fat if I go for longer periods at a lesser intensity.

Replies

  • TeenaMarina
    TeenaMarina Posts: 420 Member
    I'd love to know the answer to this, because I've worked out both ways. Seems easier to go longer sometimes and not push as hard.
  • Egger29
    Egger29 Posts: 14,741 Member
    There is an inverse proportion between fat Calories burned and exercise intensity.

    Say for example you workout for an hour at 25% intensity and burn 50 calories. At 25% intensity, 75% of the calorie burn comes from Fat which means you'll have burned approx 32.5 Fat Calories in your workout.

    Now say you do a higher intensity workout at 75% for 20 mins and burn 300 Calories. At 75% intensity, only 25% of your calorie burn will come from fat, however 25% of 300 is 75 Calores!

    So despite the shorter duration, at the higher intensity you will still burn More fat than at the lower intensity....not to mention the additional benefits to your heart and lungs from training within your target heart zones.
  • I am also curious!
  • chrisdavey
    chrisdavey Posts: 9,834 Member
    There is an inverse proportion between fat Calories burned and exercise intensity.

    Say for example you workout for an hour at 25% intensity and burn 50 calories. At 25% intensity, 75% of the calorie burn comes from Fat which means you'll have burned approx 32.5 Fat Calories in your workout.

    Now say you do a higher intensity workout at 75% for 20 mins and burn 300 Calories. At 75% intensity, only 25% of your calorie burn will come from fat, however 25% of 300 is 75 Calores!

    So despite the shorter duration, at the higher intensity you will still burn More fat than at the lower intensity....not to mention the additional benefits to your heart and lungs from training within your target heart zones.

    Good response :)

    One of the coaches I know said this to me "If your Mum can do it, you shouldn't" :tongue:
  • Seginns
    Seginns Posts: 39
    Thanks, Egger29. Very helpful info.
This discussion has been closed.